This Chandra image clearly locates a pulsar exactly at the geometric center of the supernova remnant known as G11.2-0.3. Chandra provides very strong evidence that
the pulsar was formed in the supernova of 386 AD, which
was witnessed by Chinese astronomers. Determining the
true ages of astronomical objects is notoriously
difficult, and for this reason, historical records of
supernovas are of great importance. If confirmed, this
will be only the second pulsar to be clearly associated
with a historic event.

Since pulsars are known to move rapidly away from
where they are formed, Chandra's ability to pinpoint
the pulsar at the center of the remnant implies the
system must be very young, since not enough time has
elapsed for the pulsar to travel far from its
birthplace. The Chandra observations of G11.2-0.3 have
also, for the first time, revealed the bizarre
appearance of the pulsar wind nebula at the center of
the supernova remnant. Its rough cigar-like shape is in
contrast to the graceful arcs observed around the Crab
and Vela pulsars. However, together with those pulsars,
G11.2-0.3 demonstrates that such complicated structures
are ubiquitous around young pulsars.

Chandra observed G11.2-0.3 with the Advanced CCD
Imaging Spectrometer at two epochs: August 6, 2000, and
October 15, 2000, for approximately 20,000 and 15,000
seconds respectively.